ATHENS (AFP) - Riot police were dispatched on Saturday to put down a riot at Greece's main migrant detention camp where detainees hurled stones at officers and set fire to their living quarters, authorities said.

Television footage showed fires blazing at the Amygdaleza detention camp outside Athens, where some 1,200 mainly Asian migrants are kept under police guard.

"We have 10 police officers injured by stones and other objects thrown at them," a police spokesman told AFP.

"The detainees set fire to mattresses and their living quarters, but riot police have been sent and the situation is calming down," he said.

Amygdaleza is one of several detention camps set up since last year to assist in the repatriation of thousands of undocumented migrants.

The police spokesman said rioting began when the detainees were told that their maximum stay in the camp would be extended to 18 months from a year previously.

Rights groups charge that the migrants have been subjected to abuse by police in the camps, and are denied proper healthcare.

Last week, leftist rights group KEERFA said Muslim detainees had been beaten by guards during prayers.

In July, the same group reported the death of an Afghan detainee from a pulmonary infection which his guards had allegedly ignored for months.

Greece is a major entry point into the European Union for migrants and refugees fleeing war-torn or impoverished countries in Africa, the Middle East and the Indian subcontinent.